I think these World rankings are based on the last TWO seasons of results. Therefore, since Denkova & Staviyisky had a much better season LAST YEAR than Navka & Kostamorov, that accounts for them being in first place now.

I don't know if they've changed them, but the results used to be based on the previous three year results. The current year is weighted the most, three years ago the least. Certain competitions, ie Worlds, are also worth more than others. D&S were far ahead of N&K in 2002, and they split spots last year. It would make sense for them to be ahead.